Climate Science Glossary

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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Positives and negatives of global warming

What the science says...

Climate Myth...

It's not bad
"Two thousand years of published human histories say that warm periods were good for people. It was the harsh, unstable Dark Ages and Little Ice Age that brought bigger storms, untimely frost, widespread famine and plagues of disease." (Dennis Avery)

Here’s a list of cause and effect relationships, showing that most climate change impacts will confer few or no benefits, but may do great harm at considerable cost.

Agriculture

While CO2 is essential for plant growth, all agriculture depends also on steady water supplies, and climate change is likely to disrupt those supplies through floods and droughts. It has been suggested that higher latitudes – Siberia, for example – may become productive due to global warming, but the soil in Arctic and bordering territories is very poor, and the amount of sunlight reaching the ground in summer will not change because it is governed by the tilt of the earth. Agriculture can also be disrupted by wildfires and changes in seasonal periodicity, which is already taking place, and changes to grasslands and water supplies could impact grazing and welfare of domestic livestock. Increased warming may also have a greater effect on countries whose climate is already near or at a temperature limit over which yields reduce or crops fail – in the tropics or sub-Sahara, for example.

Health

Warmer winters would mean fewer deaths, particularly among vulnerable groups like the aged. However, the same groups are also vulnerable to additional heat, and deaths attributable to heatwaves are expected to be approximately five times as great as winter deaths prevented. It is widely believed that warmer climes will encourage migration of disease-bearing insects like mosquitoes and malaria is already appearing in places it hasn’t been seen before.

Polar Melting

While the opening of a year-round ice free Arctic passage between the Atlantic and Pacific oceans would confer some commercial benefits, these are considerably outweighed by the negatives. Detrimental effects include loss of polar bear habitat and increased mobile ice hazards to shipping. The loss of ice albedo (the reflection of heat), causing the ocean to absorb more heat, is also a positive feedback; the warming waters increase glacier and Greenland ice cap melt, as well as raising the temperature of Arctic tundra, which then releases methane, a very potent greenhouse gas (methane is also released from the sea-bed, where it is trapped in ice-crystals called clathrates). Melting of the Antarctic ice shelves is predicted to add further to sea-level rise with no benefits accruing.

Ocean Acidification

A cause for considerable concern, there appear to be no benefits to the change in pH of the oceans. This process is caused by additional CO2 being absorbed in the water, and may have severe destabilising effects on the entire oceanic food-chain.

Melting Glaciers

The effects of glaciers melting are largely detrimental, the principle impact being that many millions of people (one-sixth of the world’s population) depend on fresh water supplied each year by natural spring melt and regrowth cycles and those water supplies – drinking water, agriculture – may fail.

Sea Level Rise

Many parts of the world are low-lying and will be severely affected by modest sea rises. Rice paddies are being inundated with salt water, which destroys the crops. Seawater is contaminating rivers as it mixes with fresh water further upstream, and aquifers are becoming polluted. Given that the IPCC did not include melt-water from the Greenland and Antarctic ice-caps due to uncertainties at that time, estimates of sea-level rise are feared to considerably underestimate the scale of the problem. There are no proposed benefits to sea-level rise.

Environmental

Positive effects of climate change may include greener rainforests and enhanced plant growth in the Amazon, increased vegitation in northern latitudes and possible increases in plankton biomass in some parts of the ocean. Negative responses may include further growth of oxygen poor ocean zones, contamination or exhaustion of fresh water, increased incidence of natural fires, extensive vegetation die-off due to droughts, increased risk of coral extinction, decline in global photoplankton, changes in migration patterns of birds and animals, changes in seasonal periodicity, disruption to food chains and species loss.

Economic

The economic impacts of climate change may be catastrophic, while there have been very few benefits projected at all. The Stern report made clear the overall pattern of economic distress, and while the specific numbers may be contested, the costs of climate change were far in excess of the costs of preventing it. Certain scenarios projected in the IPCC AR4 report would witness massive migration as low-lying countries were flooded. Disruptions to global trade, transport, energy supplies and labour markets, banking and finance, investment and insurance, would all wreak havoc on the stability of both developed and developing nations. Markets would endure increased volatility and institutional investors such as pension funds and insurance companies would experience considerable difficulty.

Developing countries, some of which are already embroiled in military conflict, may be drawn into larger and more protracted disputes over water, energy supplies or food, all of which may disrupt economic growth at a time when developing countries are beset by more egregious manifestations of climate change. It is widely accepted that the detrimental effects of climate change will be visited largely on the countries least equipped to adapt, socially or economically.

Comments

Hapivibe @ 44 - Also, if fossil fuels are running out, does this timing coincide nicely with the need to reduce the use of fossil fuels?

Easily accessible oil may be running out, but there's plenty of coal, tar sands and shale left. Enough perhaps, to turn the Earth into a rather different looking planet.

Finally, I would love an assurance that the people on this site putting masses of effort into collating data and facts actually live in a sustainable way ie. you practice what you profess

Yup, but by no means an "eco-saint". It's a very long list of practices my wife and I undertake to reduce our carbon output, but I don't judge others badly because they don't put in the same effort. Hopefully we'll all get there in the end (fingers crossed!)

hi jurphy
thanks for getting back to me and thanks for your interest:
i think the smoking analogy has gone off topic a bit so i wont reply directly to that

i propose that the rainforest and the sea are far away from westerners who comment on this site. species extinction does not affect us directly nor are we told when we are consuming more than our fair share and it is sadly only a minority of people take direct action to change things. global warming is a more frightening concept as it may affect all of us indiscriminately and therefore is has captured the imagination of people as an issue and it may get more media coverage due to this pscychological aspect than the other issues i proposed.

I have no data. I am telling you what i see but i hope you will allow me to write what i see as it doesn't say all comments must be backed up by data anywhere on this site, does it?

Well, hapivibe, to me "would have thought" sounds kind of like "assume." We all know what "assume" means.

I can tell you that in my case we have a bit of computer gear here that necessarily runs all the time, having to do w/offsite backup. Problem, eh? Especially it's a problem because while the local climate means that a little less than 90% of our juice comes from hydro, the same climate means that photovoltaic systems are not affordable for much more than crosswalk flashers and things on that scale. What does work here is domestic hot water preheat via solar collectors, so I installed a system that eliminates a substantial amount of electrical input for hot water heating, thus indirectly eliminating about twice the electricity consumed by the 24/7 computer hardware.

What's great about the DHW thing is the knock-on, catalytic effect it had on some of our other behaviors around the house. The absolute consumption (~1000kWh/year) of the computer hardware versus the DHW output reminded us of how just a few extra things turned off add up over time. In my mind, turning off unnecessary load sort of equates to more sunlight on the solar collectors. Strange, but that's psychology.

Meanwhile, this next couple of years will be most interesting because we've got two automobiles that are arguably ready for retirement. They've reached 20+ years of age and while they're in good repair and don't have the lousiest gas consumption, we're finally at the point where buying an electric vehicle is no longer going to be a technology application experiment folded into day-to-day living. Given our typical requirements for driving, this means we'll shortly no longer have to purchase gasoline except in those rare instances when we decide to rent a IC car for road trips. A big win there.

That leaves as usual the problem of air travel, the huge, airy elephant in the room. This is a nice example of how we're embedded in context and the dilemmas that can pose. While many of my relatives in the U.K. are dead, some are not. They are sort of a case of an "endangered species" but all the same I have qualms about visits. We go over that way about every 3 years on average, which is definitely not sustainable when we generalize and consider the hundreds of millions of aging aunts and the like pining for visits from nephews, grandchildren, etc. That's a toughie, it's an inheritance and difficult to just turn off.

that's true - let me expand. what i mean is we can't see into the sea to see it's health or how depleted it is - it's pretty mysterious as we only see the surface. not sure why i said we don't live near the sea, that was a mistake. i meant we are not close to the drift nets, for example that plunder it. we don't see that.

re. rainforest i really mean amazon rainforest. is the rainforest close to you reducing in size or is it protected?

Hapivibe - that's true - let me expand. what i mean is we can't see into the sea to see it's health or how depleted it is - it's pretty mysterious as we only see the surface

I'm now in my 4th decade of diving. I live in New Zealand. I can tell you the sea life is diminishing. Overfishing is responsible for the spread of sea urchin barrens here, because the main predator, crayfish (spiny lobster) and snapper, populations have plummeted. The effects of nutrient run-off (nitrates & phosphates predominately) and siltation are also apparent in inner harbor waters.

New Zealand is often trundled out as a poster child for sustainable fisheries management. I shudder to think what is happening in other parts of the world.

Hapivibe - I should have further explained what a sea urchin barren is - when the sea urchin populations increase to such an extent they strip the shallow coastal waters of kelp and other seaweeds - hence a barren seascape.

hapivibe wrote : "I have no data. I am telling you what i see but i hope you will allow me to write what i see as it doesn't say all comments must be backed up by data anywhere on this site, does it?"

Of course you don't need data for everything you write but you did come on here suggesting that there was an obsession with data and AGW, to the detriment of those other causes you mentioned. Now, it would appear that you don't actually have any proof of that - it is just your observation of this site and what you see in the real world ?

Well, we can all use our own experiences to come up with our own opinions (especially with regard to AGW, over-fishing, the destruction of the rainforests, etc.) but those opinions are more credible and reliable when they are based on some form of fact, evidence, data, etc.
I don't need to directly experience any of those to generally accept that the problems exist and need to be faced sooner rather than later.

Anyway, have you looked at the Intermediate version of this thread ? There are more linkages (and links) given there between AGW and all the causes you mention, showing that they are not seen in isolation or as mutually exclusive and separate.

hi jmurphy
I have already said I know they are not mutually exclusive. That is really not what i am saying.

What I am saying is the sea runing out of fish by overfishing may be a more pressing issue than AGW/CC as it may affect humans more and first.

Don't you think this is equally as big an issue? Do you think overfishing receives less coverage even though it is just as important as AGW/CC. Maybe it is more important. Do you know? Does anyone know? Has this been raised before on this site - does this mean it is being overshadowed?

happivibe wrote : "What I am saying is the sea runing out of fish by overfishing may be a more pressing issue than AGW/CC as it may affect humans more and first.
Don't you think this is equally as big an issue? Do you think overfishing receives less coverage even though it is just as important as AGW/CC. Maybe it is more important. Do you know? Does anyone know? Has this been raised before on this site - does this mean it is being overshadowed?"

There is also this study, which shows fish size decreasing, in relation to global warming - perhaps related to the smaller fish sizes being noticed in connection with what is normally regarded as being solely due to overfishing :

But, even here on Skeptical Science, there is a link given on this thread which will take you to ClimateShifts.org, who "cover a range of other threats like overfishing and pollution and other aspects of marine biology and coral reef science".

So, not ignored or lessened in importance or overshadowed, really : just the nature of this site, so to speak.

This web site is unbelievably passionate and detailed to the tune that it comes across as believing that global warming is the biggest threat facing humanity. Where is the evidence for this? I know it's a threat but is it definitely, beyond doubt the biggest threat?

I would hate all this effort to go to waste if we realised too late that overconsumption, for example is the biggest threat and the focus on global warming means we are taking our eye off the ball.

Is the biggest threat not over consumption? Should we all be debating about how to consume less and do more to change things for the better?

Thanks JMurphy, I know what this web site is about and I am still trying to figure out if the activity is in or out of proportion to the threat posed by GW. As I said in earlier comments, perhaps taking more action is better than sitting at a computer typing about it. Perhaps the biggest threat facing humanity is apathy - I don't know.

hapivibe wrote : "This web site is unbelievably passionate and detailed to the tune that it comes across as believing that global warming is the biggest threat facing humanity. Where is the evidence for this? I know it's a threat but is it definitely, beyond doubt the biggest threat?
I would hate all this effort to go to waste if we realised too late that overconsumption, for example is the biggest threat and the focus on global warming means we are taking our eye off the ball.
Is the biggest threat not over consumption? Should we all be debating about how to consume less and do more to change things for the better?"

Global warming is a threat alongside and above all the other causes you seem to be trying to emphasise as greater threats (without any evidence so far).

I have already given you examples of how AGW is connected with the rainforest and fishing, and it is also linked to availability of drinking water, coastal habitation, agriculture, etc., etc. Each on its own is a serious problem but AGW has detrimental effects on all of them. Surely that warrants special attention, since it's mitigation will have consequent benefits for all the concerns you have ?

As for over-consumption, that will continue for as long as there are goods to consume and there are goods that can be made to be consumed. Again, AGW will have an effect on that because our carbon-based economies make over-consumption easier and cheaper to carry out - while polluting the atmosphere.

Anyway, many people have many different opinions as to which threats are most important, and there's even a WIKIPIDIA page which lists them all.

There is also a UN organisation (UN DESA) which tries to join-up reaction and help to all of them, including AGW.

In other words, don't worry about us here (on a site pertaining to AGW) not spending too much time on all those other matters - there are many others out there who are. Perhaps that is where you should be addressing your questions ?

No, i'm sorry. You have not provided evidence that proves that global warming is the biggest threat. And I still don't know why there is so much attention paid to it compared to the other issues. You have not shown me a link to a discussion site where people are this involved for any other topic. Why does this topic generate a disproportionate amount of interest? Can you just give straight answers if possible and not links this time as I don't need links? Thank you.

We talk about climate change because this is a website about climate change.

This is one of those basic rules of web etiquette. The web is a big place. If you want to talk about overfishing or poodle-grooming or sports or whatever, there are plenty of other sites elsewhere. But going to a discussion forum dedicated to Topic X and telling people that they really ought to be discussing Topic Y instead is generally not appreciated.

Sorry I know I am curious and I couldn't find a section on the site. Let's say I'm sceptical about being sceptical about being sceptical but an answer would be good as I am interested in any psychological aspect. If you are in the gw 'bubble', it is indeed an open forum where I can enter and challenge this and I appreciate it. Sorry for any offence and I do honour web etiquette.

hapivibe - I have to agree with Ned. This site is dedicated to discussing/dissecting the "skeptic" response to global warming, which involves a great deal of bad logic, cherry-picking, and some very odd approaches to science.

Overfishing is a big problem. So is population growth, resource overutilization, and any number of other topics. But those topics are not what this website is devoted to, unless those are related to global warming. They are simply off-topic and inappropriate here; and it feels like you're nagging participants for putting energy into this discussion.

hapivibe > You have not provided evidence that proves that global warming is the biggest threat.

The goal of this site is not to rank every threat faced by mankind. I'm not sure what the point of such a ranking would be anyways. Are you implying that humanity is only capable of dealing with a single issue at a time? Should we halt all cancer research until we solve overconsumption or whatever issue you feel tops the "worst threat" ranking?

There are over 6 billion people on this earth, I think we can deal with more than one issue at a time.

There is a lot of discussion of AGW because the science is being actively debated (I would say more like attacked) by a large and influential group of skeptics. Breast cancer for example does not require this discussion, as nobody seriously doubts that it is real and thus there is no discussion to be had.

If you find AGW so unworthy of discussion, then tell me, why are you here adding to it? If you would rather discuss overconsumption, then visit a blog about overconsumption, or better yet, start your own. If you can generate some interesting and compelling discussion then your pet issue will attract more attention, and more power to you if it does.

You said, on an inappropriate thread, that the proper argument was whether or not CO2 was dangerous, and that where humans are has nothing to do with anything.

Briefly: there's a very good chance that warming will decrease global land ice and cause thermal expansion of the world's oceans. The resulting sea level rises would then force significant numbers of people away from their coastal homes. In some cases, the rise may cause significant migrations of people over national borders. Nationalist attitudes in target countries will hinder this migration and intensify the migratory pressure. Forced migration will be in addition to the pressure of migration by choice, as people with means will choose to move northward to avoid the longer, hotter summers.

John, "bait" is a pretty strong word for this situation. That's a pretty tired worm, and, as a fish, I'm to the point where I don't have the heart to bite this one even gently.

@ DSL (70) Don't blame John for that one. The, um, moderator was trying to keep from having to delete archiesteel's comments and to provide a teaching moment at the same time. I'm sure the moderator would appreciate it if you can think of a more appropriate way to have handled it.. And I'm sure the same mod appreciates you taking 'the road to Loch Lomond' (the high road). ;)

Like many other cities, Norfolk was built on filled-in marsh. Now that fill is settling and compacting. In addition, the city is in an area where significant natural sinking of land is occurring. The result is that Norfolk has experienced the highest relative increase in sea level on the East Coast — 14.5 inches since 1930, according to readings by the Sewells Point naval station here.

After 2-3 of months that you could call summer, and 3 months of autumn when it just gets progressively colder and darker, winter has now struck my home country (Sweden).

Six degrees warmer would be very nice now (actually would be nice the whole year around), but it still would not take the temperature above freezing in Stockholm - and I don't have the time to wait for it another 100 years for it to happen... And with the present rate of 0.016 degrees per year the promised change would hardly be noticed.

Yes, I know there are places on the earth where it is too hot, but it is hard to believe right now. New cold records were just set in Wales (-18C) and in Northern Ireland. In northern Sweden we have had temperatures around -30C for about a week already.

You may wish to reconsider that wish for an additional 6 degrees (I assume you mean C). Here's the latest, which says we're on track for 4 degrees C - by the 2060s. This means the 2 degree C target for organizations like Copenhagen or 350.org or CO2Now is impossible.

"At four degrees another tipping point is almost certain to be crossed; indeed, it could happen much earlier. (This reinforces the determination of many environmental groups, and indeed the entire EU, to bring us in within the two degrees target.) This moment comes as the hundreds of billions of tonnes of carbon locked up in Arctic permafrost – particularly in Siberia – enter the melt zone, releasing globally warming methane and carbon dioxide in immense quantities. No one knows how rapidly this might happen, or what its effect might be on global temperatures, but this scientific uncertainty is surely cause for concern and not complacency. The whole Arctic Ocean ice cap will also disappear, leaving the North Pole as open water for the first time in at least three million years. Extinction for polar bears and other ice-dependent species will now be a certainty.

The south polar ice cap may also be badly affected – the West Antarctic ice sheet could lift loose from its bedrock and collapse as warming ocean waters nibble away at its base, much of which is anchored below current sea levels. This would eventually add another 5m to global sea levels – again, the timescale is uncertain, but as sea level rise accelerates coastlines will be in a constant state of flux. Whole areas, and indeed whole island nations, will be submerged.

In Europe, new deserts will be spreading in Italy, Spain, Greece and Turkey: the Sahara will have effectively leapt the Straits of Gibraltar. In Switzerland, summer temperatures may hit 48C, more reminiscent of Baghdad than Basel. The Alps will be so denuded of snow and ice that they resemble the rocky moonscapes of today’s High Atlas – glaciers will only persist on the highest peaks such as Mont Blanc. The sort of climate experienced today in Marrakech will be experienced in southern England, with summer temperatures in the home counties reaching a searing 45C. Europe’s population may be forced into a “great trek” north."

Remember that 2 degrees C means Middle Eastern summer temps for Europe and guarantees the eventual loss of the GIS and the South American glaciers. Three degrees C risks the loss of the Amazon to fire.

Don't think for a second that it will stop there, at 4 degrees C.
4 by the 2060s means 6 by 2100 and an eventual methane clathrate/hydrate release.
Think PETM...

I quote from Met Office:
"Last night saw November minimum temperature records fall across the country. Most notably both Wales and Northern Ireland recorded the coldest November night since records began. In Wales, temperatures fell to -18.0 °C at Llysdinam, near Llandrindod Wells, Powys. Northern Ireland recorded -9.5 °C at Loch Fea."

Or check he article for yourself:
http://www.metoffice.gov.uk/corporate/pressoffice/2010/pr20101128.html

Courtesy of /.../ (NOAA), the news media has been full of reports in the last few days about last month being the “hottest June” yet recorded and 2010 being on track likewise to be the hottest year. /.../
When, however, actual temperature readings reveal record cold, this apparently is not news. So it was in May, when much of Europe was experiencing unseasonably cold weather. Germany, for instance, was hit with major snowstorms in May. In the middle of the month, the German Weather Service quietly acknowledged that the country was experiencing record cold: some 3-5 degrees Celsius below the long-term averages.
And so it was also last week, when the Georg von Neumayer polar research station on the Antarctic coast recorded the lowest temperature reading since the station was first established in 1981: minus 50.2 degrees Celsius. Unquote

It is winter again, and so the cherry-picking of cold temperatures, some of theme records, begins.

Global warming, for now, does not mean the cessation of cold weather. Nor does it mean the end of winter (the planet is still tilted from the vertical)or that no record cold temperatures will be measured anywhere.

What is does mean is that the planet as a whole is warming, and that fewer record lows will be set. That is a fact, and is exactly what has been happening.

Another fact, until recently, 19 countries around the globe had set all-time record high temperatures in 2010, compared to zero record cold lows. See here. Maybe we will hit 20 before the year is out....

@Argus: we're used to such freezing cold here in Quebec (temperatures here are on average colder than in Sweden, even though we're more to the South), but so far the late Autumn has been quite mild. Nowhere near record cold here, despite being the land of Snow and Ice... :-)

@SRJ: that's insane! There was a *25C* degree difference between Greenland's center and its western coast.

You, it seems, do not wish to "see" the warming, and to that end latch onto every cold record to convince yourself that the warming is not occurring. Doing so is cherry-picking.

The data and the scientists are not lying or deceiving you, nor are the scientists cherry-picking, they are looking at all the data. This is what Dr. Meehl had to say:

“Despite the increasing number of record highs, there will still be occasional periods of record cold, Meehl notes.

"One of the messages of this study is that you still get cold days," Meehl says. "Winter still comes. Even in a much warmer climate, we're setting record low minimum temperatures on a few days each year. But the odds are shifting so there's a much better chance of daily record highs instead of lows."

Now that is the truth. You can choose to ignore it or distort it, but doing so does not change the facts nor the truth.

And the cold weather currently affecting parts of Europe, is very much in the news.

Response: Argus and everybody else, please put further comments about cooling on a more appropriate thread--even if you are responding to a comment on this thread.

Yes-- Joe Romm at CP has been featuring some of the results. Hopefully some of the papers will be discussed here at SS.

They are pretty sobering papers in the special issue, and telling that they are now looking at a warming of +4 C or higher by 2100 and focusing on some of the high-end emission scenarios as BAU continues.

Here is a rather objective way to portray this question of hot vs. cold.

The high temp anomalies (marked at right) appear in more recent years. I've been playing with this type of display for GISSTemp data; its quite revealing. There's no dependence on wanting to see one thing or the other; its there in plain sight.

Sorry, you'll have to do better than the UK Telegraph. You snagged, out of context, a journalist's interview of a 'campaigner'. If you read the full sentence, he refers to 'resource wars' with large loss of life, not 'global warming killing billions.'

Let's set some ground rules, or this will get stupid very quickly: Try looking at the actual research. Avoid misquotes, headlines and sound-bytes. If you want to be taken seriously, that is. Then we'll talk.

You asked for examples of hyperbole and I gave you one. If you look back at my original post you'll see I never said anything about hyperbole in peer reviewed papers, so I'm not exactly sure why you insist that I look only in the "actual research" for examples. I'm talking about people in the field making statements that in my opinion are hyperbole, regardless of venue. For example, when James Hansen says that CEOs of energy companies "should be tried for high crimes against humanity and nature" I would call that an example of hyperbole. The fact that he did not make the statement in a peer reviewed paper is irrelevant. He is a scientist in the field making statements that are non-scientific and arguably designed solely to garner press.

Now, if you want to talk about why I believe that our understanding of climate sensitivity is insufficient to justify drastic action on climate change right now, I'll be happy to limit my links to actual research (or at the very least, links to sites like Real Climate that discuss actual research).

@Nederland: there is plenty of hyperbole on the denier side, with accusations of planned genocide and conspiracy theories involving a secret cabal of scientists and world government, etc.

Considering that hyperbole is enough to convince you of the invalidity of a theory, will the blatant and repeated examples on the denier side turn you off of their position as well?

In any case, hyperbole in itself is not a logical fallacy, neither are ad hominem if you don't use them in order to attack someone's credibility. The sentence "2+2=4, you arse!" may be uncouth and rude, but it's mathematically correct...

Considering that hyperbole is enough to convince you of the invalidity of a theory

I never said that hyperbole was enough to convince me of the invalidity of a theory. In fact, I never said that I that AGW theory was invalid. I think it would be helpful if you understood my position before posting.

Again, the science is quite sound - climate sensitivity is very likely to be within the 2.5-4.5C range. If you don't believe this, then you have to provide concrete, peer-reviewed evidence to the contrary.

"Warmer means more like the world that we evolved in during the PETM (when prosimians first appear) in Asia."

"We are from a tropical paradise, no polar ice caps and green pole to pole. Which do we wan't for our offspring? Warm and abundant or cold and starvation?"

Things have changed a little in the past 250 million years. Modern humans have been around for what, 250 thousand years?

I suppose you could also say we evolved in any climate since life began on earth.
But the real point you are missing is the rate of change. Changes are happening in a human lifetime that normally would take thousands of years. And at no time in man's history were there 6 billion people with highly industrialized infrastructure near the coastline, burning a hundred million years worth of sequestered carbon and putting it back into the atmosphere. We are not nomadic hunter gatherers who can pick up our tents and move to higher ground or more hospitable climates. We depend on extensive modern agriculture, much of which is in coastal plains.

Bruce Frykman

"For the record "peer review" is simply a call for rudimentary error checking - it is not thesis confirming and it is by no means systematic, thorough, or even unbiased"

I don't think anyone claims the peer review process is perfect. But I don't think you can claim the IPCC reports have not been thoroughly peer reviewed.

"Nicholls, a professor at Monash University in Victoria, Australia, said the IPCC 2007 Fourth Assessment report was subjected to several rigorous tiers of review. The study cites over 10,000 papers from the scientific literature, "most of which have already been through the peer-review process to get into the scientific literature."

"The report went through four separate reviews and received 90,000 comments from 2,500 reviewers, all of which are publicly available, along with the responses of the authors, Nicholls said."

... scientists unveiled a hypothetical California scenario that describes a storm that could produce up to 10 feet of rain, cause extensive flooding (in many cases overwhelming the state’s flood-protection system) and result in more than $300 billion in damage.

...

"We think this event happens once every 100 or 200 years or so, which puts it in the same category as our big San Andreas earthquakes. The ARkStorm is essentially two historic storms (January 1969 and February 1986) put back to back in a scientifically plausible way. The model is not an extremely extreme event."